The present invention is directed to a device for laterally adjusting conveyors, i.e transport devices, for flat products in rotary presses, such as in belt movers for transporting products in folders configured subsequent to web-processing rotary presses.
Conveyor belt movers in folding apparatuses are known from JP HEI 7-8364. It provides for belt movers in the folder, which is disposed downstream from a rotary press, to be used at the second longitudinal folding device for flat products. Printed products to be provided with a second longitudinal fold are inserted by a vertically up-and-down movable folding blade into the fold nip between two folding rollers underneath a feeder table. To position the products to be folded above the folding roller nip, the products are gripped on both sides and carried up to positioning stops, prior to the back parts of the products to be folded being pushed into the nip of the folding rollers.
EP Patent 0 553 739 B 1 describes a device for adjusting sheet guide elements in rotary presses. It discusses a device for adjusting sheet hold-down devices, which are movable by a drive transversely to the sheet travel path and include carriers and pressing elements. The hold-down devices are mounted on a rotatable shaft and engage with oppositely directed, helical slits on the shaft. A longitudinally slit, frame-fixed, hollow member is provided, upon which rings encircle its periphery in a sliding-type arrangement. These rings each carry a sheet hold-down device, and, together with the hollow member, they provide a locking against rotation. The rings each have a guide pin directed toward the inside of the hollow member. Mounted inside of the hollow member is a shaft that is rotatably supported at its ends. On its first half length, the shaft has at least two helical slits of different pitches, which are mirror-inverted with respect to at least two helical slits on a second half length of the shaft. Assigned to each slit is a ring, which has a ring-fixed guide pin that engages in the slit with force- and form-locking, the pitch of the slits towards the ends of the rotatable shafts decreasing.
To ensure a damage-free product transfer when it comes to belt movers used for transporting flat products in folders of web-processing rotary presses, it has been established that a precise adaptation of the distance between the transport belts conveying the products is of great importance.
In consideration of the approaches known from the related art, the object of the present invention is to devise a method for adjusting product-delivery devices in press folders, which will enable the position of the product-delivery device to be adapted to the format or size of the folded product.
The present invention provides a device for adjusting conveyors for printing presses that process flat products or for further processing units (40) arranged downstream therefrom, in which are accommodated belt movers (1) containing a plurality of individual belts (5) for transporting the flat products. The belt movers are guided via guide rollers (6) and setting rollers (7), and driven via a drive (2), and the tension in the individual belts (5) is kept constant via tensioning devices (3). Accommodated in the further processing unit (40) are shafts (16, 28, 34) having stationary elements (25, 31, 39) which guide the individual belts (5) and on which are supported, symmetrically with respect to the machine center (13), movable receiving elements (20, 27, 36), which guide, drive, and retain under constant prestressing, the individual belts (5).
The advantages associated with the approach of the present invention can be seen, above all, in that all of the elements that convey, prestress, as well as drive the individual belts of a belt mover, are now simultaneously adjusted in the lateral direction. By varying the duration of the driving of the drive effecting the lateral adjustment motion, different travel paths may be implemented, so that the belt mover width may be adapted to all current folded product formats to be processed, at a second longitudinal folding device within a folder arranged downstream from a rotary press. Since it is ensured that all the elements supporting the individual belts of a belt mover are driven around the same paths with respect to the machine center, a strictly parallel positioning of all individual belts of a belt mover in relation to one another is ensured. This substantially improves the folding accuracy, since there are now no longer forces acting in a direction perpendicular to the product delivery direction on the products to be folded. A substantially greater product quality is able to be achieved due to the precision feeding of the printing sheets to be folded and their delay at stops, before there is a downward movement of a folding blade within the second longitudinal folding device.
The individual belts of a belt mover of elements that, as the case may be, are guiding, driving, and retained under initial stress, may advantageously be indirectly or directly driven on shafts. If sufficient installation space is available within the folder, i.e., in the second longitudinal folding device, then the driving elements may be indirectly adjusted at their shafts, for example using adjusting forks, while, in accordance with one alternative specific embodiment, guide rollers for the individual belts of a belt mover may be driven directly at the shafts accommodating them.
Besides accommodating the elements that guide, drive, or prestress the individual belts of a belt mover, in an individual type of construction, pairs or groups of elements that guide, drive, or hold under constant prestressing the individual belts are also able to be accommodated at the receiving elements that are able to be driven laterally with respect to the product delivery device. They may be supported so as to be relatively movable on cylindrical or slide-type receiving bodies, the cylindrical or slide-type receiving bodies being able to be driven indirectly or directly at the shafts supporting them.
In one embodiment of the idea underlying the present invention, for purposes of lateral adjustment, the cylindrical or slide-type receiving elements may be provided with spindle drives having contrary-sense threaded sections. Using the pitch of the contrary-sense threaded sections, exact travel paths of the individual receiving elements, whether they be configured in a slide-type or cylindrical shape, are able to be achieved with respect to the machine center.
The slide-type receiving elements, at which the cylinders that retain the individual belts of the belt movers under constant prestressing may be accommodated, may be individually penetrated by the threaded spindle sections of different pitches. The adjusting forks surrounding the cylindrical elements may also be rotatably accommodated at the spindle-shaped drive elements indirectly driving the cylindrical receiving elements. In another variant of an embodiment of the idea underlying the present invention, the receiving elements guiding the individual belts are themselves able to be directly driven on contrary-sense threaded sections of the adjusting shaft. To this end, the adjusting shaft may be provided, symmetrically with respect to the machine center, with stationary elements guiding the individual belts, and, on both sides of their mid-section, have conically tapered sections, which, for their part, may be provided with threaded sections of different pitches.
In this variant of an embodiment, the receiving elements used for guiding the individual belts are secured by an anti-rotation element in the further processing unit, at its side walls, in order to prevent an unwanted change in the lateral position of each of the individual belts of the conveyor belt movers with respect to one another.
The elements situated in relation to the stationary components and used for guiding, driving, and constant prestressing, may be driven laterally, individually, or also, in pairs.
The device proposed by the present invention for adjusting delivery elements for transporting flat products may be used for sheet-processing rotary presses, whether it be for conventional offset presses or also for digitally operating sheet-fed presses. It is particularly significant for folders, in which, in web-processing rotary presses, folded products, printed on one side or multiple sides, are produced, and are then provided with a second longitudinal fold in a second longitudinal folding device. The design accuracy of the device plays a decisive role in the product quality. Relative movements are not allowed to occur in the belt mover gripping the product on both sides, before the product is longitudinally folded, by pushing the folding spine into the cooperating jackets of a folding roller pair.